A race meeting at Werribee has been cancelled because of extreme heat forecast in Victoria.

Monday's meeting had already been brought forward to start in the morning to try to avoid the high temperatures but the forecast has been revised to reach 39 degrees at 11am and a high of 43 by 2pm.

Racing Victoria consulted all participants before calling the races off in the interests of horse and human welfare.

RV said horses engaged at Werribee may be entered as extended nominations by 4pm on Sunday for the Victorian meetings on New Year's Day, with acceptances for those meetings taken on Monday morning.